Pressure vessel with internal self sealing door

ABSTRACT

A pressure vessel closing system for conducting industrial processes has a pressure vessel with an underside door opening having a major and a minor axis, a cover that is proportionally larger than the door opening, and an external door operating mechanism. The door operating mechanism has door manipulation capabilities for inward movement, rotation, lateral movement, tilting movement, and outward movement of the cover into and out of the pressure vessel through the door opening, for internally closing the door against the inner face of the door opening; the door being then self sealing from the pressure applied within the pressure vessel.

[0001] This application relates and claims priority to pending U.S. application Ser. No. 60/224461, filed Aug. 10, 2000.

FIELD OF THE INVENTION

[0002] This invention relates to pressure vessels used in industrial processes such as parts cleaning and operations requiring extreme cleanliness and operated at elevated pressures and temperatures, and in particular to a pressure vessel design and closure mechanism providing an internally self-sealing cover.

BACKGROUND

[0003] There is a general requirement in industry for conducting processes that require enclosures or pressure vessels that can be loaded with parts or other objects to be processed, permit the admittance and removal of process fluids or materials necessary to the process after the enclosure is closed, and be elevated and ranged in pressure and temperature to, in some cases, extremes, for or during the process. Some processes are much more critical as to contamination, and require quick and close control of temperature, pressure, and the volume and timing of the introduction of process fluids to the pressure vessel. Add to that the demand for conducting these processes in a production mode, and the growing sophistication of the processes themselves, and it is amply clear that improvements in pressure vessels are needed.

[0004] In many industrial applications involving the use of pressure vessels, the vessel is loaded by vertical placement through an open top port. A cover or door is typically attached by hinges to the pressure vessel, or may be unattached altogether except by the latching mechanism, being manually removed from the vessel for access to the pressure chamber. The vessel cover or door is typically closed by manually bolting or mechanically clamping or latching the process vessel flanges and cover flanges together around the perimeter of the door opening to form a pressure seal. In some cases the pressure vessel has other than an upright orientation, for example, a front loading pressure chamber. In any case, the door latching systems, in order to accommodate the high pressure requirement, are often slow or awkward to manipulate, likely to cause contamination through wear and accumulated dirt or excess lubrication in the latching and sealing mechanism, and may be susceptible to improper closure and/or mechanical failure under pressure of the external structure devoted to the latching function.

[0005] A further problem with pressure vessels in a production environment is the difficulty in adapting them to standard object handling robots or conveyor systems. Complex carriage systems are often necessary for automation of the loading and extracting of materials being processed, involving complex transitions between horizontal and vertical transport of the objects for placement in and recovery from the pressure vessel.

SUMMARY OF THE INVENTION

[0006] The invention, most simply stated, is a pressure vessel and door combination, where the door may, by manipulation, be inserted into the pressure vessel and oriented for internally sealing against the door opening so that sealing pressure is provided by the internal pressure, and is uniformly distributed around the perimeter of the door opening.

[0007] It is an object of the invention to provide an inherently robust door closure scheme for a pressure vessel for use in industrial processes, where the critical pressures are constrained to primary pressure vessel structure, namely the vessel and the door, rather than to external latches, bolts, or door operating mechanisms.

[0008] It is a further object of the invention to provide a door operating mechanism and geometry adaptable to automated production requirements, where manual intervention is not normally necessary to assure safe operating of the closure and sealing functions.

[0009] Still other objectives and advantages of the present invention will become readily apparent to those skilled in this art from the detailed description, wherein we have shown and described a preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by us on carrying out our invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a cross section view of a pressure vessel and internally sealing door, with externally hinged door operating mechanism, the door in the closed position.

[0011]FIG. 2 is a cross section view of the embodiment of FIG. 1, with the door lifted inward from the closed position in the first step of a door opening sequence.

[0012]FIG. 3 is a cross section view of the embodiment of FIG. 1, advanced from the FIG. 2 door opening sequence position, with the door rotated to align its major axis with the minor axis of the door opening.

[0013]FIG. 4 is a cross section view of the embodiment of FIG. 1, advanced from the FIG. 3 door opening sequence position, with the door being laterally displaced from the center position along its major axis.

[0014]FIG. 5 is a cross section view of the embodiment of FIG. 1, advanced from the FIG. 4 door opening sequence position, with the door being tilted on an axis parallel to its minor axis, away from the hinge point of the door operating mechanism.

[0015]FIG. 6 is a cross section view of the embodiment of FIG. 1, advanced from the FIG. 5 door opening sequence position, with the door and door operating ting mechanism being rotated progressively through four steps about the door operating mechanism hinge point, so as to uncover the pressure vessel door opening.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] Referring to FIGS. 1-6, the preferred embodiment is a pressure vessel 10 with an irregular shaped door opening 12 having a sealing edge flange 14; the opening having a major and a minor axis, the inner surface of the edge flange configured for sealing of a door 16 that is inside the pressure vessel 10, against the inner face of the door opening edge flange 14. There is a correspondingly shaped door 16 of slightly larger size than the door opening 12, operated by an external control mechanism 18, that can be manipulated for insertion through the door opening 12 into the pressure vessel 10 and be positioned for sealing against the door opening flange 14 by internal pressure, and be likewise manipulated in reverse for removal when the pressure has been relieved. The door is able to fit through the door opening because the minor axis of the door is slightly smaller than the major axis of the door opening.

[0017] For opening, the door 16 is lifted inwardly by the control mechanism 18, in this case a hinged arm arrangement off a hinge point external of the vessel and to one side of the door opening, away from the edge seal 14, and partially into the chamber of the pressure vessel 10. The hinge point may be a double jointed hinge mechanism. The door is then rotated 90 degrees by a piston or any suitable rotary actuator to align the minor axis of the door with the major axis of the opening 12. The door is then manipulated by lateral movement along a slide bar on the hinged arm by a piston or screw or other linear actuator, within the chamber and tilting as shown in the figures, so as to adjust the radial distances between the hinge point and the door edges to fit within the radial distances between the hinge point and the opening edges. The required geometry will be readily apparent to those skilled in the art. The door is then rotated about the hinge point downward so as to pass the door through the door opening and further to a fully open position, permitting access to the chamber.

[0018] The open door position may be intended solely to move the door away from the opening so as to provide clearance for access for inserting and removing objects being processed. Alternatively, the inner surface of door 16 may be adapted to holding or carrying the object under process into and out of the pressure vessel by the door operating mechanism, provided sufficient clearance for the object attached to the door has been allocated as between the door 16 and the opening 12 in calculating the operating geometry.

[0019] Alternative door operating mechanisms 18 are possible. There may be a hinged arm 20 system with door rotation and tilt capabilities, that operates from a reference point displaced to one side of the door opening, whether or not attached directly to the pressure vessel. There may be a primarily linear door motion system 22 for movement towards and away from the pressure vessel, that incorporates lateral and tilt capabilities, and is operated from a reference point spaced away from and opposing the door opening of the pressure vessel. Yet another variant of the door operating mechanism could include a rotor 24 whereby the minor axis of the door may be aligned with the major axis of the opening.

[0020] It is important to note that the door operating mechanism 18 need only be strong enough to manipulate the weight of the door and, if appropriate, any objects that may be carried by or attached to the door. The design must anticipate any significant moment forces created due to change of velocity and direction of motion of the mechanism and door in higher speed operations. The door operating mechanism 18 must be sufficiently precise to reliably align the door 16 properly against the internal sealing surface 14 prior to initializing pressurization of the closed vessel. The self sealing pressure between the door 16 and the door opening flange 14 is purely compressive, supplied by the pressure within the pressure vessel pushing the door 16 against the door opening flange 14.

[0021] The door operating mechanism 18, when the inside surface of the door 16 is equipped with a suitable cassette or object holding device, is adaptable to interface with a conveyor system or robot system for transferring objects for processing under pressure in the vessel. There is less likelihood of debris or contamination from the self sealing door operating mechanism falling into the vessel 10 or processing environment at the mouth of the vessel 12, in particular where the pressure vessel 10 is operated inverted and the door operating mechanism is vertically oriented and operated from underneath the inverted pressure vessel 10. The door operating mechanism can be further mechanically shielded from the process environment, if the user deems it useful, as by a bag or bellows arrangement. The hinge mechanism can be arranged to keep the entire door opening mechanism below the level of the door, to reduce the possibility of contamination of the process environment from debris falling off the door opening mechanism.

[0022] The invention is susceptible to many embodiments, variations, and applications. For example, it may be employed for industrial parts cleaning with CO₂, carbon dioxide, such as is commonly done for removing cutting oil from mechanical parts. Accordingly, the drawings and description of the preferred embodiment are disclosed as illustrative of the invention, and are not to be construed as restrictive.

[0023] For example, there is within the scope of the invention, a high pressure vessel and closing system for conducting industrial processes, consisting of a pressure vessel having an oval shaped underside a door opening with a major and a minor axis, and a cover of substantially the same shape but proportionally larger than the door opening, where the major axis of the opening is larger than the minor axis of the cover. There is an external door operating mechanism that has door manipulation capabilities for inward moving, rotating, laterally moving, tilting, and outward moving of the cover into and out of the pressure vessel through the door opening.

[0024] The external door operating mechanism may have an arm hinged from a hinge point external of the vessel and displaced to a side of the door opening for providing the manipulation capabilities for inward moving and outward moving, with the further manipulation capabilities for rotating, laterally moving, and tilting being mounted on the arm.

[0025] The cover may have a sealing flange disposed around its edge for contacting and sealing the cover to the interior surface of the vessel around the opening. The external door operating mechanism may be automated. The pressure vessel and closing system may be incorporated into an automated industrial production system.

[0026] Other and various embodiments within the scope of the specification and the claims that follow will be readily evident to those skilled in the art. 

We claim:
 1. A high pressure vessel and closing system for conducting industrial processes comprising a pressure vessel having an oval shaped underside a door opening, said opening having a major and a minor axis, a cover of substantially the same shape but proportionally larger than said door opening, said major axis of said opening being larger than the minor axis of said cover, an external door operating mechanism, said mechanism comprising door manipulation capabilities for inward moving, rotating, laterally moving, tilting, and outward moving of said cover into and out of said pressure vessel through said door opening.
 2. The high pressure vessel and closing system of claim 1, said external door operating mechanism comprising an arm hinged from a hinge point external of said vessel and displaced to a side of said door opening for providing said manipulation capabilities for said inward moving and said outward moving, said manipulation capabilities for said rotating, laterally moving, and tilting being mounted thereon.
 3. The high pressure vessel and closing system of claim 2, said cover comprising a sealing flange disposed around the edge thereof for contacting and sealing said cover to the interior surface of said vessel.
 4. The high pressure vessel and closing system of claim 3, wherein said external door operating mechanism is automated.
 5. The high pressure vessel and closing system of claim 4, wherein said pressure vessel is incorporated into an automated industrial production system. 